1. Field of the Invention
The present invention relates to a non-aqueous electrolyte cell comprising a positive electrode, a negative electrode and a non-aqueous electrolyte consisting of a solute and an organic solvent.
2. Description of the Prior Art
A non-aqueous electrolyte cell in which a negative electrode has lithium or a lithium alloy as an active material provides the advantages of high energy density and low self-discharge rate.
In this type of cell, a low boiling point solvent such as dimethoxyethane or dioxolane has been conventionally used as a solvent of an electrolyte. However, the solvent reacts with lithium, whereby a film, which is inactive and has a low conductivity, is formed on surfaces of the negative electrode. This causes the internal resistance of the cell to be increased, resulting in deterioration of storage characteristics (especially, a high rate discharge characteristic after storage).
In order to solve the above problem, it has been proposed to employ a solvent mixture of a cyclic carbonate and a low boiling point solvent to form a film of Li.sub.2 CO.sub.3, which has a high conductivity on surfaces of the negative electrode, thereby improving the storage characteristics. However, this does not provide satisfactory storage characteristics.